SECTION 115.178. Monitoring and Inspection Requirements

(a) At least once each calendar year, an owner or operator shall conduct an audio, visual, and olfactory inspection of each compressor seal cover for defects that may result in air emissions, except as provided in subsection (c) of this section. Defects include, but are not limited to, visible cracks, holes, or gaps in the cover, or between the cover and the separator wall; broken, cracked, or otherwise damaged seals or gaskets on cover devices; and broken or missing hatches, access covers, caps, or other cover devices. Repairs must be made in accordance with subsection (e) of this section.

(b) The following monitoring and inspection requirements apply to closed vent systems routed to a control device, including routing to a process, used to demonstrate compliance with the control requirements of this division, except as specified in subsection (c) of this section. For the purpose of this subsection, a leak is a measured volatile organic compounds (VOC) concentration of equal to or greater than 500 parts per million by volume (ppmv). Defects that could result in air emissions include visible cracks, holes, or gaps in piping; loose connections; liquid leaks; or broken or missing cover devices. Repairs of equipment with a leak or detection of a defect in equipment must be made in accordance with subsection (e) of this section.

(1) The owner or operator shall conduct initial inspection and monitoring by the appropriate compliance date listed in §115.183 of this title (relating to Compliance Schedules), using United States Environmental Protection Agency (EPA) Method 21 in 40 Code of Federal Regulations (CFR) Part 60, Appendix A-7 on all closed vent system components to demonstrate that the closed vent system operates with no leaks. The instrument response factor criteria in EPA Method 21 in 40 CFR Part 60, Section 8.1.1 must be for the average composition of the stream and not for each individual VOC constituent.

(2) The owner or operator shall conduct annual monitoring and inspections following the initial inspection conducted in paragraph (1) of this subsection.

(A) The owner or operator shall conduct an audio, visual, and olfactory inspection on closed vent system joints, seams, or other connections that are permanently or semi-permanently sealed (e.g., a welded joint between two sections of hard piping or a bolted and gasketed ducting flange) for defects that could result in air emissions. For an inspection using EPA Method 21 in 40 CFR Part 60, Appendix A-7, monitoring must be performed to demonstrate that there are no leaks following any time a component is repaired or the closed vent system connection is unsealed.

(B) The owner or operator shall monitor the closed vent system components and connections using EPA Method 21 in 40 CFR Part 60, Appendix A-7, other than those subject to subparagraph (A) of this paragraph, to demonstrate that the closed vent system operates with no leaks.

(3) The owner or operator of a closed vent system routed to a control device, including routing to a process, used to demonstrate compliance with the control requirements of this division, must conduct monitoring using EPA Method 21 in 40 CFR Part 60, Appendix A-7 to demonstrate there are no leaks from the closed vent system.

(A) The instrument response factor criteria in EPA Method 21 in 40 CFR Part 60, Section 8.1.1 must be for the average composition of the stream and not for each individual VOC constituent. For process streams that contain nitrogen, air, or other inert gases that are not VOC, the average stream response factor is calculated on an inert-free basis.

(B) An owner or operator shall calibrate the detection instrument using the procedures specified in EPA Method 21 in 40 CFR Part 60, Appendix A-7 before use on each day the instrument is used.

(C) The following calibration gases must be used.

(i) Zero air must contain less than 10 ppmv hydrocarbon in air.

(ii) The other calibration gases must be mixtures of methane or n-hexane in air, one with a concentration either of less than 10,000 ppmv, and another with a concentration of no more than 2,000 ppmv greater than the leak definition concentration of the equipment monitored. If the design of the monitoring instrument allows for multiple calibration scales, then the lower scale shall be calibrated with a calibration gas that is no higher than 2,000 ppmv above the concentration specified as a leak, and the highest scale shall be calibrated with a calibration gas that is approximately equal to 10,000 ppmv. If only one scale on an instrument will be used during monitoring, the owner or operator is not required to calibrate the scales that will not be used during monitoring that day.

(D) The owner or operator shall follow EPA Method 21 in 40 CFR Part 60, Appendix A-7 to adjust instrument readings if choosing to account for the background VOC level.

(E) Using the following parameters, the owner or operator shall determine if a potential leak interface operates with no detectable emissions. A potential leak interface is determined to operate with no detectable VOC emissions if the organic concentration value is less than 500 ppmv.

(i) If an owner or operator chooses not to adjust the detection instrument readings for the background VOC concentration level, then the maximum organic concentration value measured by the detection instrument must be compared to the 500 ppmv value for the potential leak interface.

(ii) If an owner or operator chooses to adjust the detection instrument readings for the background VOC concentration level, an owner or operator shall compare the value of the arithmetic difference between the maximum organic concentration value measured by the instrument and the background organic concentration value with the 500 ppmv value for the potential leak interface.

(c) Closed vent system components and compressor seal covers that are designated as unsafe-to-monitor or difficult-to-monitor are not subject to the inspection and monitoring frequency in subsection (b) of this section. The monitoring methods of the components and covers that apply in subsections (a) and (b) of this section apply to the components in this subsection.

(1) Unsafe-to-monitor components must be identified in a list in accordance with the requirements in §115.180 of this title (relating to Recordkeeping Requirements). If an unsafe-to-monitor component is not considered safe to monitor within a calendar year, then it must be monitored as soon as possible during times that are safe to monitor.

(2) Difficult-to-monitor components must be identified in a list in accordance with the requirements in §115.180 of this title. A difficult-to-monitor component must be inspected at least once every five years.

(d) Upon the detection of a leak, the owner or operator shall affix to the leaking component a weatherproof and readily visible tag bearing an identification number and the date the leak was detected. This tag must remain in place, or be replaced if damaged, until the leaking component is repaired. Tagging of difficult-to-monitor leaking components may be done by reference tagging. The reference tag should be located as close as possible to the leaking component and should clearly identify the leaking component and its location.

(e) The owner or operator shall repair a leak or defect as soon as practicable and shall make a first attempt to repair a leak or defect no later than five calendar days after the leak or defect is found. The component must be repaired no later than 15 calendar days after the leak or defect is found, except if a delay of repair is needed. If parts are unavailable, repair may be delayed if parts are ordered promptly. The repair must be completed within five days of receipt of the required parts. Repair may be delayed until the next shutdown if the repair of the component would require a shutdown that would create more total VOC emissions than the repair would eliminate, but the repair must be completed by the end of the next shutdown. A repair is complete once an EPA Method 21 or audio, visual, and olfactory inspection, as appropriate, under subsection (b)(2) or (3) of this section is conducted showing no leak or defect.

(f) The owner or operator shall install and maintain monitors to measure operational parameters of any control device installed to meet applicable control requirements of this division. Such monitors must be sufficient to demonstrate proper functioning of those devices to design specifications.

(1) For a direct-flame incinerator, the owner or operator shall continuously monitor the exhaust gas temperature immediately downstream of the device.

(2) For a condensation system, the owner or operator shall continuously monitor the outlet gas temperature to ensure the temperature is below the manufacturer's recommended operating temperature for controlling the VOC vapors routed to the device.

(3) For a carbon adsorption system or carbon adsorber, as defined in §101.1 of this title (relating to Definitions), the owner or operator shall, as applicable:

(A) continuously monitor the exhaust gas VOC concentration of a carbon adsorption system that regenerates the carbon bed directly to determine breakthrough, which for the purpose of this paragraph, is defined as a measured VOC concentration exceeding 100 ppmv above background expressed as methane; or

(B) switch the vent gas flow to fresh carbon at a regular predetermined time interval for a carbon adsorber or carbon adsorption system that does not regenerate the carbon directly. The time interval must be less than the carbon replacement interval determined by the maximum design flow rate and the VOC concentration in the gas stream vented to the carbon adsorption system or carbon adsorber.

(4) For a catalytic incinerator, the owner or operator shall continuously monitor the inlet and outlet gas temperature.

(5) For a vapor recovery unit, the owner or operator shall continuously monitor at least one of the following operational parameters:

(A) run-time of the compressor or motor in a vapor recovery unit;

(B) total volume of recovered vapors; or

(C) other parameters sufficient to demonstrate proper functioning to design specifications.

(6) For a control device not listed in this subsection, the owner or operator shall continuously monitor one or more operational parameters sufficient to demonstrate proper functioning of the control device to design specifications.

(g) The following inspection requirements apply to storage tanks subject to the control requirements in this division.

(1) For an internal floating roof storage tank, the internal floating roof and the primary seal and the secondary seal (if one is in service) must be visually inspected through a fixed roof inspection hatch at least once every 12 months.

(A) If the internal floating roof is not resting on the surface of the VOC inside the storage tank and is not resting on the leg supports; if liquid has accumulated on the internal floating roof; if the seal is detached; if there are holes or tears in the seal fabric; or if there are visible gaps between the seal and the wall of the storage tank, within 60 days of the inspection the owner or operator shall repair the items or shall empty and degas the storage tank in accordance with Subchapter F, Division 3 of this chapter (relating to Degassing of Storage Tanks, Transport Vessels, and Marine Vessels).

(B) If a failure identified in subparagraph (A) of this paragraph cannot be repaired within 60 days and the storage tank cannot be emptied within 60 days, the owner or operator may submit written requests for up to two extensions of up to 30 additional days each to the appropriate regional office. The owner or operator shall submit a copy to any local air pollution control program with jurisdiction. Each request for an extension must include a statement that alternate storage capacity is unavailable and a schedule that will assure that the repairs will be completed as soon as possible.

(2) For an external floating roof storage tank, the secondary seal gap must be physically measured at least once every 12 months to ensure compliance with §115.175 this title (relating to Storage Tank Control Requirements).

(A) If the secondary seal gap exceeds the limitations specified by §115.175(d) of this title, within 60 days of the inspection the owner or operator shall repair the items or shall empty and degas the storage tank in accordance with Subchapter F, Division 3 of this chapter.

(B) If a failure identified in subparagraph (A) of this paragraph cannot be repaired within 60 days and the storage tank cannot be emptied within 60 days, the owner or operator may submit written requests for up to two extensions of up to 30 additional days each to the appropriate regional office. The owner or operator shall submit a copy to any local air pollution control program with jurisdiction. Each request for an extension must include a statement that alternate storage capacity is unavailable and a schedule that will assure that the repairs will be completed as soon as possible.

(3) If the storage tank is equipped with a mechanical shoe or liquid-mounted primary seal, compliance with §115.175 of this title can be determined by visual inspection.

(4) For an external floating roof storage tank, the secondary seal must be visually inspected at least once every six months to ensure compliance with §115.175 of this title.

(A) If the external floating roof is not resting on the surface of the VOC inside the storage tank and is not resting on the leg supports; if liquid has accumulated on the external floating roof; if the seal is detached; if there are holes or tears in the seal fabric; or if there are visible gaps between the seal and the wall of the storage tank, within 60 days of the inspection the owner or operator shall repair the items or shall empty and degas the storage tank in accordance with Subchapter F, Division 3 of this chapter.

(B) If a failure identified in subparagraph (A) of this paragraph cannot be repaired within 60 days and the storage tank cannot be emptied within 60 days, the owner or operator may submit written requests for up to two extensions of up to 30 additional days each to the appropriate regional office. The owner or operator shall submit a copy to any local air pollution control program with jurisdiction. Each request for an extension must include a statement that alternate storage capacity is unavailable and a schedule that will assure that the repairs will be completed as soon as possible.

(5) The owner or operator shall conduct an audio, visual, and olfactory inspection at least once per month, separated by at least 14 calendar days, of a control device used to control the VOC emissions from a storage tank.

(6) The owner or operator shall inspect and repair all closure devices not connected to a control device according to the schedule in this paragraph.

(A) The owner or operator shall conduct an audio, visual, and olfactory inspection of each closure device not connected to a vapor recovery unit or other vapor control device to ensure compliance with §115.175(a)(1)(A) of this title. The inspection must occur when liquids are not being added to or unloaded from the tank. If the owner or operator finds the closure device open for reasons not allowed in §115.175(a)(1)(A) of this title, the owner or operator shall attempt to close the device during the inspection. The inspection must occur before the end of one business day after each opening of a thief or access hatch for sampling or gauging, and before the end of one business day after each unloading event. If multiple events occur on a single day, a single inspection within one business day after the last event is sufficient.

(B) Once per calendar quarter, the owner or operator shall conduct an audio, visual, and olfactory inspection of all gaskets and vapor sealing surfaces of each closure device not connected to a vapor recovery unit or other control device to ensure compliance with §115.175(a)(1)(B) of this title. If an improperly sealed closure device is found, the owner or operator shall follow repair requirements in accordance with §115.175(a)(1)(D) of this title. For the purpose of this subparagraph, a repair is complete if the closure device no longer exudes process gasses based on audio, visual, and olfactory means.

(h) This section does not apply to fugitive emission components required to comply with §115.177 of this title (relating to Fugitive Emission Component Requirements).

Source Note: The provisions of this §115.178 adopted to be effective July 21, 2021, 46 TexReg 4313